Great find; thanks for posting the link. Although it's not so much for my benefit; I just thought someone with more experience in the field and with a better command of the English language than me can explain things better. Andrew is spot on.

Originally Posted By: fredk

That's why companies have marketing departments, to convince you of things that just aren't so. SUVs and safety in slippery conditions are a prime example of this.

I'm sorry, but this comment is not warranted; I just post in this thread a test I did that has nothing to do with any marketing department. If you buy based on marketing don't assume everyone is doing the same.

Originally Posted By: fredk

FWIW we do have commodity amps. They're called pro amps and the most recent generation of class D amps deliver a lot of bang for the buck.

Again, in this thread, I've posted a question: why aren't everyone buying the Behringer amp that for a paltry $380 delivers no less than 1,400W into two channels and 4,000W bridged? Why would Axiom produce the ADA line of amps for a few times the price of the Behringer?And most important... why are people buying them? You cannot honestly believe that everyone not buying a pro amp is an idiot, do you?

Why would Axiom produce the ADA line of amps for a few times the price of the Behringer?

Not being an insider I cannot answer that. I would presume that Andrew's answer is at least part of the reason.

I know that several pro amps have been bench tested and shown to deliver. Danley Labs bench tested one of the recent Peavey class D amps and it performed flawlessly.

There are some legitimate reasons for not buying a pro amp. They are not exactly pretty and tend to have rather noisy fans that need to be swapped out.

I do wonder why nobody is producing a prettied up version for the consumer market.

Quote:

I just post in this thread a test I did that has nothing to do with any marketing department.

Fair enough. The only controlled test on the subject that has ever been done contradicts your findings. There are also a number of people that have attempted something resembling double blind listening tests that contradict your findings. What should I make of that?

Quote:

You cannot honestly believe that everyone not buying a pro amp is an idiot, do you?

Absolutely not. I do believe that lots of people have been convinced of something that is not there in an expensive amp. That is a very different thing than thinking somebody is an idiot.

I guess I will continue to believe that all competently designed amps sound the same and you will continue to believe that there is a real difference. As long as we are both happy...

_________________________
Fred

-------Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!

I know that several pro amps have been bench tested and shown to deliver. Danley Labs bench tested one of the recent Peavey class D amps and it performed flawlessly.

I do wonder why nobody is producing a prettied up version for the consumer market.

I'm pretty sure that there are pro amps out there that are very, very good, including the one you mentioned; I wasn't knocking out this particular type of amps... sorry if my post gave you that impression. That's why I mentioned that particular brand/model. And, I believe there are some that fit your description for home use; I have a loaned one from a friend - ATI 1540, and it sounds pretty good.

Originally Posted By: fredk

Fair enough. The only controlled test on the subject that has ever been done contradicts your findings. There are also a number of people that have attempted something resembling double blind listening tests that contradict your findings. What should I make of that?

It's obvious for me that one should try if possible and do some tests for him/her self as any tests out there have a dose of subjectivism attached, especially when dealing with sound quality. Mine included; there is no way that you should take someone else words as facts.

Quote:

I guess I will continue to believe that all competently designed amps sound the same and you will continue to believe that there is a real difference. As long as we are both happy...

I took the liberty of highlighting a word in you above quote; this is exactly what I was trying to say but used different words (i.e. same-class). I have to repeat myself: one cannot make blank statement that all amps are the same, regardless of type, manufacturer, specs or price.

Again, Adrian, we're all saying the same thing when it comes to competently. That's why I don't include your RCA receiver in my specification. I'm choosing receivers and amps that enthusiasts are likely to own; a midrange Denon or Onkyo would fit my spec just fine. Then using that receiver as a preamp for the amp reduces variables.

Great find; thanks for posting the link. Although it's not so much for my benefit; I just thought someone with more experience in the field and with a better command of the English language than me can explain things better. Andrew is spot on.

Originally Posted By: fredk

That's why companies have marketing departments, to convince you of things that just aren't so. SUVs and safety in slippery conditions are a prime example of this.

I'm sorry, but this comment is not warranted; I just post in this thread a test I did that has nothing to do with any marketing department. If you buy based on marketing don't assume everyone is doing the same.

Originally Posted By: fredk

FWIW we do have commodity amps. They're called pro amps and the most recent generation of class D amps deliver a lot of bang for the buck.

Again, in this thread, I've posted a question: why aren't everyone buying the Behringer amp that for a paltry $380 delivers no less than 1,400W into two channels and 4,000W bridged? Why would Axiom produce the ADA line of amps for a few times the price of the Behringer?And most important... why are people buying them? You cannot honestly believe that everyone not buying a pro amp is an idiot, do you?

With pro amps like the Behringer they can have noisy fans because they can operate at very hot temperatures (especially when you push them). The fans raise the rooms noise floor quite substantially in a residential environment. The fans are detrimental to sound quality so most people swap them out with a quieter after market version. Most pro amps are designed to live with higher noise floor and distortion than say the ADA amps. With pro amps output impedance might be high enough to affect the frequency response of the loudspeaker. Or even frequency response non-linearities at increasing power output levels. Bench tests are really important for pro amps. It won't tell you everything how the amp will sound but it will indeed show problems. The quality of pro amps varies substantially in the market even within the Behringer line from model to model. Pro amps are definitely not for everyone and amps like the ADA certainly have some trade-off advantages over them.

_________________________
I’m armed and I’m drinking. You don’t want to listen to advice from me, amigo.

OK now this thread is getting interesting! I really need to ask for clarification on something: is this thread about amps or amplification in general? It certainly seems that some people talking in this thread seem to think that these are the same thing. In fact they are quite different. Then there seems to be another misunderstanding - that "Pro amp" means the same as "cheap amp". I personally own no cheap amp but do own a Pro amp - a Bryston 7B ST which I picked up used earlier this year. I don't think anyone on here would call it cheap but yet it is often used in Pro applications such as recording studios.By nature, the amplification built into a receiver represents an engineering compromise. To be competitive the receiver can only weigh so much, be so big, and cost so much. So the amount of heat that can be dissipated is only so much, and the parts budget is limited, and so on. This means that the amplification capabilities of the best receivers are simply not as good as the better separate amps. In fact it shouldn't be surprising if all but the worst separate amps are as good as or better than the amp circuits in receivers.

I certainly found this to be true when I compared my Denon receiver to my ADA 1500. The ADA1500 simply blows away the amp circuits in my Denon. No contest!

Comparing different separate amps like the ADA and a Bryston or Emotiva, however, would be a much more interesting exercise. However it is unlikely that a cheap amp would hold its own in such a test. Nor would any receiver.

Adrian. Even Behringer makes some good amps. The EP2400/4000 even deliver into a 2 ohm load. Their Inuke class D is supposed to deliver the goods as well, but I have not seen any bench test results.

Peavey's IPR series is another new class D contender that delivers. That is the one Danley bench (and torture) tested with no audible distortion.

On paper, pro amps have higher distortion levels, but I do not think that we can distinguish between the tiny amount of distortion a good pro amp exhibits and the infinitesimal distortion an expensive audiophile amp exhibits.

Both the Inuke and IPR are new in the last year or so and are very inexpensive for the power they deliver. I wonder if the Class D world has drastically changed?

I may have missed your comments on competently designed so maybe we agree there. I personally think that many of the newer receivers fit into the competently designed category.

_________________________
Fred

-------Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!

Pro-amps are excellent value with lots of power and obviously , a great bang for the buck. I am using a QSC in an instrument/PA application, however, I really could never use it for HT because, as has already been mentioned a number of times, the fan noise out of these units is just too distracting. The models I believe most are talking about are at the lower end of the price range, however, if you want that amp to be quieter at the same or better power levels, you have to move up the model and price range with that manufacturer and because these pro-amps generally only are available in mono or stereo, with having to buy two or three of these higher end units, it would close the gap considerably in money spent compared to a quality dedicated HT multi-channel power amp.

For those who continue to recommend or even gush about how great these cheap "Pro" amps are, I have only one question: Have you actually heard one and compared its performance on real music material against a good quality separate amplifier driving good quality speakers like the Axiom M80's or LFR's?